H.Shim/JournalofMaterialsProcessingTechnology121(2002)116±122121

Fig.11.Evolutionofoptimalblankdesignstages:(a)initialshape(Numisheet'99);(b)2nddesign;(c)3rddesign(optimal

blank).

Acknowledgements

ThisworkwassupportedbytheBrainKorea21Project.References

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15±32.

4.Conclusion

Asystematicmethodofoptimalblankdesignbasedonthesensitivityanalysishasbeenappliedtothedrawingsofarbitraryshape.Fromtheresultofdeformationprocessanalysis,shapesensitivityhasbeenobtainednumerically.Withtheshapesensitivity,initialblankhasbeenmodi®edinordertoobtainthedesiredshape.Thenumericalandexperi-mentalresultsdemonstratethatthepresentmethodprovidesexcellentpredictionofblankshapeandtheblankshapegivesthetargetshapealmostexactly.Throughtheinvestigationtheproposedsystematicmethodofoptimalblankdesignisfoundtobeveryeffective.